PON1 and dementia: In that study, PON1 activity and genotype were assessed as predictors of cognition and brain atrophy in individuals with MCI (78-year-olds, n = 196, 60% women) who had an MMSE score > 24/30 and no evidence of dementia and were subjected to B vitamin (n = 95; daily oral supplement tablets with folic acid, vitamin B12, and B6) or placebo (n = 101) treatment for two years.